Conventionally, a display device in which a touch panel is stacked on a display panel has been in widespread use. Further, a configuration in which a touch panel is incorporated in a display panel has been proposed. For example, US 2010/0001973A discloses a touch screen that includes display pixels having capacitive elements.
In a conventional touch panel, lines that convey signals of electrodes for detecting a touch are arranged outside a sensor area. For example, FIG. 6B and paragraph 0099 of US 2010/0001973A indicate that metal lines are arranged in a frame area of a touch screen.